This is a hand blocked halo band, the shape held on French millinery wire invisibly secured from the inside. It is is a wonderful slightly ombre, red parisisal with a swirl in the same material. 
I created a lily from matching soft leather and trimmed with a very fine veil.
It is secured with an elastic to go under your hair at the back of your head. After arduous research (happy hat wearing) I am convinced that this is the most comfortable and secure way to keep a hat on so you can focus on looking great and socialising rather than worrying about a wobbly hat!
The image of the model wearing the same hat shape (made on a halo band block to my specifications) to give you an idea of how it sits on a real head.